A team of Iowa State University researchers discovered that it may be possible to successfully grow alfalfa on Mars. The group has published a paper describing their work on the open-access site PLOS ONE.
As various groups around the world consider not only sending humans to Mars, but also building shelters on the Red Planet that could sustain them indefinitely, work on ways to make such projects a reality continues. Such projects face numerous challenges before they can become a reality, one of which is figuring out how to feed people who live so far away. Growing food inside of protected enclosures is one possibility that is receiving a lot of attention.Of course, such enclosures would have to mimic Earth’s conditions, as the plants grown there would have to come from here.
Growing plants on Mars will necessitate a few basic elements, including soil, water, food, and sunlight. The researchers focused on the first two in this new effort. Mars does not have much soil, instead relying on basalt, a type of volcanic rock. Basalt contains few, if any, ingredients that plants can use as food, and it is rocky rather than loamy. Growing food in it would thus necessitate both altering the basalt and using plants that are best suited to its use.
The researchers tried growing several types of crop plants in finely ground basalt found on Earth in this new effort. Plants such as turnips, lettuce, and radishes did not grow well as a result. On the other hand, they discovered that alfalfa performed exceptionally well. The researchers also discovered that if they grew alfalfa in a basalt plot and then planted other crops in the same basalt patch, the other crops fared much better.Turnip yields, for example, increased by 311%.
The researchers then focused on water, which is extremely scarce on Mars. It is mostly found in polar ice. Because the water is so salty, it cannot be used to grow plants. They used a type of bacteria known as Synechococcus, which can desalinate water, to reduce the saltiness of water samples from Earth. Testing revealed that it could significantly reduce salt concentrations, but not sufficiently to be used on plants. The water sample was then further filtered by pouring it through piles of basalt rocks—enough, they discovered, to be used in plant growth.